An outbreak of waterborne cryptosporidiosis caused by post-treatment contamination

作者：Huw Vaughan Smith, W. J. Patterson, R. Hardie, Lindsey A. Greene, Charles V. Benton, W. J. Tulloch, R. A. Gilmour, R. W. A. Girdwood, J. C. M. Sharp, Gerald I. Forbes · 发表于：Epidemiology and Infection · 年份：1989 · DOI：10.1017/s0950268800031101 · 被引用次数：108 · 研究领域：Parasitic Infections and Diagnostics、Amoebic Infections and Treatments、Legionella and Acanthamoeba research

An outbreak of waterborne cryptosporidiosis affecting 27 persons, diagnosed stool positive, occurred in Ayrshire in April 1988. Twenty-one in 27 confirmed cases required some form of fluid replacement therapy. Local general practitioners indicated a two- to fivefold increase in diarrhoeal disease during the outbreak, and following enquiries made by Environmental Health Officers it became apparent that many hundreds of people had suffered a diarrhoeal illness at that time. Cryptosporidium spp. oocysts were detected in the treated chlorinated water supply system, in the absence of faecal bacterial indicators. Oocyst contamination of a break-pressure tank containing final water for distribution was the cause of this waterborne outbreak. An irregular seepage of oocyst-containing water, which increased during heavy rains, was the cause of the break-pressure tank contamination, rather than a failure of the water-treatment processes. The waterborne route should be considered when clusters of cryptosporidiosis-associated with potable water occur. Waterborne cryptosporidiosis can occur in the absence of other faecal indicators of contamination.